#include <bits/stdc++.h>
#define rep(i,a,b) for (int (i)=(a);(i)<(b);++(i))
#define sz(x) (x).size()
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef pair<int,int> P;
const int INF = 1e9;
const ll LINF = 1LL<<60;
const ll MOD = 1e9+7;

int N;
queue<int> A[1000];

int main() {
  cin>>N;
  int sum = 0;
  rep(i,0,N) {
    int P; cin >>P;
    sum += P;
    rep(j,0,P) {
      int a; cin>>a;
      A[i].push(a);
    }
  }
  while (sum > 0) {
    rep(i,0,N) {
      if (!A[i].empty()) {
        int a = A[i].front(); A[i].pop();
        if (sum > 1) cout << a << ' ';
        else cout << a;
        --sum;
      }
    }
  }
  return 0;
}